This invention relates generally to removable inkjet print cartridges, and more specifically to the proper positioning of print cartridges on a carriage.
Numerous performance and reliability problems can result if a removable print cartridge is not properly positioned, mounted and held by a carriage in a printing system. These may include inconsistent electrical connections, premature flex circuit failures, misplaced ink droplets on print media, and other resulting deficiencies such as ink deprime problems in the print cartridge which prevent satisfactory ink ejection from the print cartridge. Such reliability is especially important in low cost monochrome type printers which are used to print point-of-sale receipts.
The rapid acceleration and deceleration of a scanning carriage can also cause a print cartridge to rock or change position in a carriage unless it is securely clamped into a proper printing location against positional datums in a carriage chute.
When a print cartridge reservoir is depleted, proper cartridge removal and replacement should be self explanatory without having to follow complicated instructions The cartridge should be easily accessible for removal. The position of a newly installed cartridge should be repeatable each time without any necessary calibration. Partial installation should be easily avoided, and any handle should therefore tend to remain in either an open or close position rather than somewhere in between.
A unique printing system has been developed which incorporates one or more print cartridges individually mounted in their own separate carriages which scan back and forth across media in a print zone
The printer carriage has a cavity or chute for removable mounting of the print cartridge, and includes a set of support guides on a floor and a set of datums on a forward wall of the chute for positioning the print cartridge. A spring-loaded clamp is movable by a handle between a latched open position which allows easy insertion and withdrawal of the print cartridge from the chute, and a closed position which applies a clamping force against a back wall of the print cartridge. When the clamp is unlatched, a biasing spring pivots the clamp about an axis into the closed position such that a clamping force is applied in both a forward and downward direction against a lower portion of the back wall of the installed print cartridge to securely hold the print cartridge in the chute against the datums, and to facilitate conductive contact through a plurality of electrical interconnects between the carriage and the print cartridge.
A method of installation or removal of a print cartridge employs access along a vertical path through an open top of the chute when the clamp is in the open position. A printing system with the carriage and print cartridge expels ink along an approximately horizontal path from an upstanding nozzle plate while the clamp is in the closed position.